Question on power requierments (AV StarJet)
 

Hi Guys,


A few years ago... I started a Aviation Design StarJet project... but it fell to the wayside because I didn't have a good engine for it. I know the old JPX engines were crazy heavy... and I think the first version only put out 8~9 Lbs. (then up to 12 lbs later on)


Anyway... I decided to pull it out, and get it going again.


Right now... I have a little Wren 44 gold (10lbs) in a CM Pro T-45. It was a fun project, but I don't fly it much because they have a nasty tip stall habit, and I don't want to kill my engine. (The airframe was only $120, so I'm not worried about that) Because of that... I've been looking for a new home for my Wren.

Then... I started thinking about the starjet. Since the early JPX was less than 10 lbs... I figure that my Wren may fly it. So... after weighing everything... the airframe built, with servos, battery's, retracts... and so on... weighs in at 9lb 14oz. I figure about 4 Lbs for the wren installed, with 32 oz of fuel. That would give us a take-off weigh of less than 14 Lbs.


So what do you guys think? Will 10 Lbs of thrust fly a 14lb model? (The startjet is supposedly a very efficient airframe) AND... if I go out and buy a 60N turbine... sure, I will have an extra 3~4 lbs thrust... but the install will be a solid 2~2.5 Lbs heavier. (plus need more fuel for the same 6 min flight)




http://img.photobucket.com/albums/v9...s/100_3081.jpg

Should fly fine, my first jet was about 22 pounds wet at take off with an 11 pound thrust RAM 500 and it flew fine once on step..

OK.... I just found this from an old thread.....





So... since the instructions say this jet can weigh 7.5Kg (16.5 Lbs) with the old JPX... and that it can fly on the JPX 240 at 8 Lbs... I guess 10 Lbs and less weight should be good.


I guess I'll start working on it again this week.